This invention relates generally to electrical controls and in particular to an electrical switch and a method of calibrating a bimetal strip.
In the past, various types of electric switches have been utilized as starting relays for various types of electric motors, such as for instance those known as permanent split capacitor types. Generally, these permanent split capacitor type motors have characteristics affording relatively high torque at normal running speeds and lower power consumption, but with the capacitor connected in the motor circuit, generally relatively poor starting torque is encountered. In the event of a locked rotor condition, as may be encountered in some motor applications or usages, rather high current may be drawn by the motor which may have a deleterious affect on the electric switch being utilized as a motor starting relay. This condition may, of course, be considered as a disadvantageous or undesirable feature of at least some of the past electrical switches. Another one of the disadvantageous or undesirable features of at least some of these past electrical switches is believed to be that they were not automatically calibrated or at least they did not lend themselves readily to calibration. Another disadvantageous or undesirable feature of some of the past electrical switches is believed to be that they did not lend themselves to effect immediate restarting of the motor after a line or power interruption.